Please ask hosters where to set upload_max_filesize 30M and post_max_size 30M. If in .htaccess then you will need to add to this file (it is in the root) lines:
php_value upload_max_filesize 30M
php_value post_max_size 30M
If there is a if there is php.ini that can be edited then you need to add
register_globals = Off
upload_max_filesize=30M
post_max_size=30M
